Apparatus for recording electrical signals



Aug. 18. 1925. 1,550,048

s RUBEN APPARATUS FOR RECORDING ELECTRICAL SIGNALS Filed June 17, 1922 11 c |||||l llllllllll r INVENTQR ATTORNEY tus Patented A... '18, 1925.

UNITED STATES v 1,550,948 PATENT OFFICE. I

sweat nunnnpor new roan, n. Y.

APPARATUS FOR RECORDING ELECTRICAL SIGNALS.

Application file c1 June 17, 1922. Serial No. 569,093.

To all whom it may concern:

graphic signals into permanent, visible impresslons upon a fluid absorbing surface.

Its object is to provide a simple and eflicient means of translating received electrical impulse signals into permanently recorded readable symbols.

The apparatusconsists broadly, of a device similarto a pen, equipped with two opposing electrodes, such as a penpoint and another metal point located adjacent to the point of the pen with suitable conductive leads to terminals 'to-be connected in an electrical circuit, and means of discharging from one of the electrodes a fluid, through which, under the control of received electrical impulse signals, current is discharged between the electrodes, the fluid being electrochemically responsive by color change, in its path upon the surface upon which it is impressed.

Its operation is based upon the known fact that in certain solutions, such as potassiuln-iodide, when subjected to an electrical discharge, an electrochemical reaction occurs, changing them from practically colorless substances to those having prononnced colors. This reaction has been utilized inv recording telegraph signals, the most common practice being to saturate the paper in the form of a strip, in a solution of potassium-iodide and pass it between two electrodes, between which the electrical impulse signalsare discharged. At those intervals in the strip passing during the discharges, permanent dark colored sectionsof the chemically changed solution are recorded, corresponding to such discharges. This apparais not readily'portable and the strips mustibe constantly saturated to. be useful.

In accordance with this invention, the apparatus comprises a fluid carrier, similar to a pen, carrying a solution of potassiumio'dide, or the like, the n point acting as an electrode, the o posing electrodebeing conveniently locate so that current discharging between the two electrodes, passes through the fluid delivered from its source, at the impression surface. Suitable means are provided for connecting the electrodes to a radio or telegraph line receiving circuit.

As the apparatus passes across a paper or otherimpression surface, or if it is placed in a fixed position and a similar surface passed in contact with it, the fluid therefrom is impressed upon the surface, and the current discharging between the electrodes, in response to incoming signal impulses, changes the fluid from a practically colorless material at the positive electrode, to a dark line on the surface. If the current flows in the form-of pulsations, as in telegraph signals, as the electrode passes across the surface, the pulsations are indicated by the short and long line equivalents of the telegraph dots and dashes. Both electrodes must be in contact with the fluid, preferably in its path on the surface. But if it isdesired to decrease the surface friction, one of the electrodes can be raised slightly above the surface, so long as'it remains in contact with the fluid. By this method of recording, the recording medium is supplied in a moist condition as required.

In order to afford a full understanding of the principles of the invention, one. embodiment of the apparatus in an especially desirable practical form, is illustrated in the accompanying drawings, andis hereinafter described indetail for the sake of a concrete illustrative example; but it is to beunderstood that the invention is not limited to theparticular arrangement or specific type. 0 apparatus.

Referring to the drawings, Fig. 1 shows one form ofthe apparatus with the wires and terminals for connecting the electrodes in -a receiving circuit.

Fig. 2 is a diagram showing the same form of apparatus as a part of a radio receiv ng circult.

Referring to Fig. 1, at 1 is a pen point as an electrode .connected by wire 5 to one of the terminals 7, and at 2 is placed the opposing electrode, connected by wire 6to the other terminal at. 7 for connection in a receiving circuit. '1 At 3 is-one end of a fountain. pen, in which the pen point is inserted,

and having a hole through it affording a from the'fluid reservoir, along the v passage pen point. .sented by 4.

- I Referri he wall of the pen repreng to Fig. 2, 5 "and ,6 mpresentpthe lead wires from the fountain pen recorder, connected with the terminals of a radio receiving circuit, and with a vacuum tube amplifier 10, and the input terminals of a transformer -8, connected in a commonly ,known form of receiving circuit in which by a moist line of such a solution as'po- I tassium-iodide,

traced by the pen drawn across the surface. An electrochemical re action will thenoocur in the line so traced, changing it from an almost colorless one to a dark brown line which will continue so ;long as the pen is propelled and the fluid flowing and the current discharging be tween the electrodes. If'the current discharge is interrupted, the dark line is interrupted, the colorless line displacing, or rather, succeeding it.

When the grid in tube 10 is charged negatively by battery 13, it will electrostatically oppose the electron current through the vacuous space between the-electron emission element and the plate in tube 10. The potential is so adjusted that normally no current, or an amount insufficient to effect the chemical reaction, will flow through the tube, that then, as the pen is passed across the paper surface, only the colorless line ap pears.

If now a positive potential is applied to the grid circuit, as from the transformer 8,

trode in said circuit, and

and therefore through the circuit, so'

it will neutralize the n ative effect in the grid, and a current will ow in the tube and pen circuit, permitting a recurrence of the electrochemical reaction in the potassiumiodide.

As the primary is connected in an electrical circuit, such as a radio receiving circuit, electrical impulses discharged through the primary will be transferred to the secondary, and when in a positive direction, will cause a flow of current through the circuit when the pen is passed across the surface, affording a path thereon for the discharge, causing an electrochemical reaction in the path of the moist potassium-iodide. Dots and dashes of the signal code will thus ocour in the fluid line, directly in response to such signal impulses, yielding a permanent record of incoming messages. To record signals at higher speeds, it is necessary merely to pass the pen over the impression surface at higher speed.

VVha-t I claim is,

In combination with a self-feeding pen adapted to contain an electro-chemically responsive color-changing liquid and having an electrically conducting pen point adapted to discharge said liquid upon a contacting surface and to be connected as an electrode in an electrical circuit, another electrically conducting element attached to said pen and adapted to be connected as an opposing elecadapted to'be, simultaneously with said other electrode, in electrical contact with said liquid discharged from said pen uponsaid contacting surface.

Signed at New York, in the county of New York and State of New York this 15th day of June A. D. 1922.

SAMUEL RUBEN. 

